Images from Space: Satellites and Sensors

Credit: NASA

The A-Train Constellation: Near-simultaneous observations from multiple instruments

World’s longest running satellite data collection program

Landsat Applications National Land Cover Database (NLCD)

Endless Possibilities • Habitat mapping • Mapping flood

plains • Wildfire impacts • Nearshore

bathymetry

• Watershed management

• Coral reef health • Invasive species monitoring

• Disaster management

• Agricultural insurance fraud

• Deforestation • Wildlife corridors • Impervious surfaces

• Mapping geologic landforms

• Cartographic mapping

• Renewable energy siting

And on and on. . .

• Part of the Copernicus Program - the European Union’s Earth Observation Program

• Several 2-satellite constellations are active or in development:

- Sentinel 1A/B

- Sentinel 2A/B

- Sentinel 3A/B

- Sentinel 4

- Sentinel 5

- Sentinel 6

Sentinel

Satellite Constellation – Two or more satellites in complimentary orbital planes that work together as a system.

Satellite Constellation

GPS Satellite Constellation. 24 Satellites in 6 Orbital Planes RapidEye Constellation. 5 Satellites in 1 Orbital Plane

Benefits: • Redundant Sensor • Better temporal resolution (revist time)

Sentinel 1A/B

Credit: ESA

Instrument Swath Width Resolution

Synthetic Aperture Radar (SAR) 80km; 250km; 400km 5x5m; 5x20m; 25x100m

Launch: • April, 2014; April, 2016

Uses: • Radar imaging of sea ice, land movement and marine

environment; Sea surface winds; Wave height

Mission: • Radar imaging of land and

water

Sentinel 2A/B

Credit: ESA

Instrument Swath Width

Spatial Spectral Revisit

MultiSpectral Instrument (MSI)

290km 10m, 20m, 60m 13 Band 5 Days at equator

Uses: • Land cover change

• Spatial planning

• Global agriculture

• Forest/vegetation monitoring

• Flood mapping and risk assessment

Launch: • June, 2015; March, 2016

Mission: • Land monitoring with optical

imagery

Sentinel 3A/B

Credit: ESA

Instrument Swath Width

Spatial Spectral Revisit

OCLI 1,270km 300m 21 Bands < 2 days at

equator

SLSTR 1,420km 500m (VIS, SWIR); 1km (MWIR, TIR)

9 Band < 1 day at equator

Uses: • Land and Ocean color

• Global and regional land and surface temperature

• Pollution monitoring

Launch: • February, 2016; April, 2018

Mission: • Marine Observation

Sentinel 4 • Air quality trace gases and

aerosols

Sentinel 5

Sentinel 6

• Atmospheric measurements with high spatio-temporal resolution

• Radar altimeter to measure global sea surface height

Commercial Satellites

Platform Spatial Spectral Revisit

Optical Sensor

Assembly (OSA)

0.8m Panchromatic

4m Multispectral

5 Bands 3 Days

INFO: • Launched September, 1999;

retired 2015 • First commercial high

resolution sensor

USES: • Base maps • Environmental monitoring

Land Remote Sensing Policy Act – October, 1992. Enabled American companies to operate imaging satellites in space.

IKONOS-1, Washington DC, October, 1999

IKONOS-1

Commercial Satellites

SPOT - Satellite Pour l’Observation de la Terre

Platform Spatial Spectral Revisit

SPOT 6 & 7

1.5m Panchromatic

6m Multispectral

5 Bands Daily

INFO: • SPOT 1 launched February, 1986

- 10-20m resolution

• SPOT 7 launched June, 2014

• Another pioneer of commercial satellite market

‐ Can collect stereo pairs using scenes form adjacent paths

USES: • Base maps • Environmental monitoring

SPOT 7 Image, Fiji

Commercial Satellites WorldView-3

INFO: • Launched August, 2014

• First multi-payload, super spectral, high-resolution commercial satellite

USES: • Base maps

• Agriculture

• Environmental monitoring

• Mining

Platform Spatial Spectral Revisit

WorldView-3

0.31m Panchromatic; 1.2m Multispectral;

3.7m SWIR; 30m CAVIS

1 Panchromatic 8 multispectral

8 SWIR 12 CAVIS

1 day

Credit: Digital Globe, WV-3. U.S. Capitol 30cm

Commercial Satellites

Satellite Swath Width

Spatial Bands Revisit

QuickBird, 2001 16.8km 0.61m Pan; 2.62m MS 5 3.5 Days; Daily

Oblique

RapidEye, 2008 77km 5m 5 5.5 Days Nadir; Daily Oblique

GeoEye-1, 2008 15.2km 0.4m Pan; 1.65m MS 5 3 Days; Varies

Oblique

Pleiades-1A/B, 2011 20km 0.5m Pan; 2m MS 5 Daily

Many Others:

• Resolutions and revisit times continue to improve

• Public/Private partnerships

• Large image archives still available for decommissioned satellites

Commercial Satellites

CubeSat

• Design proposed 1999 by researchers from CA Polytechnic State U. and Stamford U.

• Satellite are composed of blocks 10cm x 10cm x 11.5cm with each cube weighing no more than 1.3kg (1U 6U)

• Often built with off-the-shelf electronic components and processors

• Often launched as “multiples”

Design standards reduce research and deployment costs .

First launched in 2003, there were over 900 deployed in orbit by Jan., 2019

Commercial Satellites

SkySat

• Based on CubeSat concept, but scaled up to about the size of a small fridge

• 15 satellites deployed.

• 0.7m Pan; 1m MS

• 5 Band

• Can capture Pan video 30-120 sec.

Credit: SkySat. Tripoli, Libya

Commercial Satellites

PlanetScope

• Based on CubeSat concept - 3U sizing

• 200+ individual “doves” deployed as a series of “flocks”

• 3.7m; 4 Band; Daily revisit

Watching a Satellite Deploy: https://www.planet.com/pulse/whats-it-like-to-watch-a-satellite-deploy/

Instrument Spatial Spectral

CZCS 0.8km 6 Band

SeaWiFS 1.1km 8 Band

Marine Sensors

SeaWiFS – Sea-Viewing Wide Field-of-View Sensor

INFO: • 1997 – 2010 • Expanded on CZCS • Sensor could be tilted to avoid glint over

equatorial regions

USES: • Global ocean biologic ocean data

CZCS – Coastal Zone Color Scanner

INFO: • 1978 – 1986 • Beginning of Ocean color imagery

USES: • Chlorophyll concentration; Sediment distribution;

Salinity; Temperature; Ocean currents

SeaWiFS

SeaWiFS Chlorophyll Concentration

NASA’s Earth Observing System

Instrument Swath Width Spatial Spectral Revisit

MODIS 2,330km 200m (bands 1-2); 500m (bands3-7);

1000m (bands 8-36) 36 Band 1-2 Days

Aqua Launch: • May, 2002 • Crosses Equator in PM

Terra Launch: • December, 1999 • Crosses equator in AM

Marine Sensors

VIIRS – Visible Infrared Imaging Radiometer Suite

Launch: • October, 2011 • Rides on Suomi NPP

satellite

USES: • Designed to replace

aging MODIS sensors • Ocean color; Ocean/Land

temperature; Ice movement; Fires; Clouds and aerosols

Instrument Swath Width

Spatial Spectral Revisit

VIIRS 3,060km 375m (6 I-Bands);

750m (16 M-Bands) 22 Band 16 Days

Marine Sensors

NASA. Suomi NPP

Accessing Imagery: Commercial Satellite Vendors and Resellers

Dozens of Options: - Satellite Imaging

Corporation

- Harris Geospatial

- LANDinfo

• As a buyer you will be responsible for defining all parameters of the imagery you need – AOI; cloud coverage; timeframe; etc.

• In addition to the area covered, cost will often depend on whether the imagery exists in the archive or if new tasking is required.

Temporal Requirements?

SST, 4µ Night, Daily SST, 4µ Night, 8-Day SST, 4µ Night, Monthly

SST, 4µ Night, Monthly Climatology (2002-2018)

Climatology = Composite/Summary/Average over specified timeframe

• Project needs will determine choice and level of processing needed

Data Pre-Processing?

https://oceancolor.gsfc.nasa.gov/

Level 1&2 Browser

https://oceancolor.gsfc.nasa.gov/

Level 3 Browser

USGS Earth Explorer

https://earthexplorer.usgs.gov/

Image Access: USGS LandsatLook Viewer

https://landlook.usgs.gov/viewer.html • Access Landsat and Sentinel-2 images

Image Access: Sentinel

https://scihub.copernicus.eu/dhus/#/home

Resources

50 Satellites you need to know: Earth Satellite List https://gisgeography.com/earth-satellite-list/

NASA Ocean Color https://oceancolor.gsfc.nasa.gov/

USGS Earth Explorer https://earthexplorer.usgs.gov/

USGS Landsat Look https://landlook.usgs.gov/viewer.html

Copernicus Open Access Hub https://scihub.copernicus.eu/dhus/#/home